Sarah U Morton1, Kaitlyn Brettin2, Henry A Feldman3, Kristen T Leeman4. 1. Division of Newborn Medicine, Department of Pediatrics, Boston Children's Hospital, Boston, MA, 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA, 02115, USA. Electronic address: sarah.morton@childrens.harvard.edu. 2. Harvard Medical School, Boston, MA, 02115, USA. 3. Division of Newborn Medicine, Department of Pediatrics, Boston Children's Hospital, Boston, MA, 02115, USA; Institutional Centers for Clinical and Translational Research, Boston Children's Hospital, Boston, MA, 02115, USA. 4. Division of Newborn Medicine, Department of Pediatrics, Boston Children's Hospital, Boston, MA, 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA, 02115, USA.
Abstract
BACKGROUND: Nucleated red blood cells (nRBCs) are associated with adverse outcomes for pediatric and adult intensive care patients. METHODS: The association between nRBC count and mortality was examined in an observational cohort of patients admitted to the neonatal intensive care unit from December 2015-December 2018. RESULTS: Among the 1059 patients with at least one nRBC count obtained, 45 infants (4.2%) experienced in-hospital mortality prior to NICU discharge, the primary outcome measured in this study. Infants with any nRBC count >0 had a significantly higher risk of mortality (5.3% [45/849] vs. 0% [0/351], p < 0.001 by Fisher exact), and time to mortality decreased with higher nRBC counts (Spearman correlation -0.59, p < 0.001). The association between nRBC count and mortality remained significant even when restricting only to infants who were older than 7 days at time of nRBC count. CONCLUSION: Among neonatal intensive care unit patients, including those >7 days old, nRBCs are associated with significantly elevated mortality risk. A prospective study to better characterize clinical co-variants is necessary to better establish the use of nRBCs as a predictor of mortality.
BACKGROUND: Nucleated red blood cells (nRBCs) are associated with adverse outcomes for pediatric and adult intensive care patients. METHODS: The association between nRBC count and mortality was examined in an observational cohort of patients admitted to the neonatal intensive care unit from December 2015-December 2018. RESULTS: Among the 1059 patients with at least one nRBC count obtained, 45 infants (4.2%) experienced in-hospital mortality prior to NICU discharge, the primary outcome measured in this study. Infants with any nRBC count >0 had a significantly higher risk of mortality (5.3% [45/849] vs. 0% [0/351], p < 0.001 by Fisher exact), and time to mortality decreased with higher nRBC counts (Spearman correlation -0.59, p < 0.001). The association between nRBC count and mortality remained significant even when restricting only to infants who were older than 7 days at time of nRBC count. CONCLUSION: Among neonatal intensive care unit patients, including those >7 days old, nRBCs are associated with significantly elevated mortality risk. A prospective study to better characterize clinical co-variants is necessary to better establish the use of nRBCs as a predictor of mortality.